With the World Series on the line, Chris Carpenter takes the ball on short rest tonight for the St. Louis Cardinals. Carp, who gave up four runs in three innings while pitching on short rest against the Phillies in Game Two of the NLDS, gets the nod over a fully-rested Edwin Jackson and Kyle Lohse.
Starting pitchers typically perform worse on three days' rest. Baseball-Reference keeps track of a stat called tOPS+, which compares a pitcher's on-base-plus-slugging percentage in a particular situation to his overall OPS. One-hundred is average, while anything over 100 means the pitcher did worse in that situation than he did overall. With the exception of 2009, starters have lost a good bit of their effectiveness when going on short rest:
2008: 115 tOPS+ (15 percent worse on three days' rest than in other situations)
2009: 94 tOPS+
2010: 113 tOPS+
2011: 121 tOPS+
How have pitchers fared in the playoffs on short rest? Not well. Since 2008, there have been 10 starts made on three days' rest. The pitchers lasted slightly more than 5.1 innings per start, with a solid strikeout total (7.6 per nine innings pitched) but also plenty of walks (3.8 per nine) and lots of home runs allowed (1.55 HR/9). Those starters had a collective 5.79 ERA.
The sample size is awfully small (a total of 54.1 innings pitched), but we are talking about some of the best starting pitchers in the game. After all, a manager wouldn't consider putting a pitcher out there on short rest unless he thought that his less-than-optimal-ace would still be better than a well-rested, middle-of-the-pack starter. In recent years, though, those aces have coughed up runs at a Kyle Davies-like clip.
Here's the list of short-rest playoff starters since '08, ranked by Game Score (the average is around 50):
Is 70-80 percent of vintage Chris Carpenter better than Edwin Jackson at 100 percent? We'll find out tonight, though it's entirely possible that Carp is only the nominal starter, going once through the Rangers' lineup, and Jackson sees a few innings of action as well. Given how starters tend to fare worse in the mid-to-late innings -- compared to their first time through the lineup, their opponent OPS climbs 29 points the second time through and 74 points when facing batters a third time -- being quick to the bullpen is a smart strategy.
If Game Seven is even one percent as thriling as Game Six, we'll all be in for a treat.